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				<h2 class="articleTitle">Everyday BPA Exposure Decreases Human Semen Quality</h2>
				<p id="articleDek">The more bisphenol A men were exposed to--at work or through the environment--the worse off their sperm were, according a new study that finds the link in humans</p>
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							By  <a href="http://www.scientificamerican.com/author.cfm?id=1822">Katherine Harmon</a>
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					<span class="datestamp">October 28, 2010&nbsp;|</span>
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					<span class="imageCaption"><b>MAN DOWN:</b> Levels of BPA way below those currently tolerated by government agencies seem to have negative effects on the viability of sperm.</span>
					<span class="imageCredit">Image: WIKIMEDIA COMMONS/GILBERTO SANTA ROSA</span>
				
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				<p>The common industrial chemical <a href="http://www.scientificamerican.com/podcast/episode.cfm?id=is-bpa-bad-for-you-08-10-23">bisphenol A</a> (BPA) has been <a href="http://www.scientificamerican.com/article.cfm?id=just-how-harmful-are-bisphenol-a-plastics">linked to many ills</a>, including reproductive abnormalities, <a href="http://www.scientificamerican.com/article.cfm?id=chemical-in-consumer-plastics-linked-to-heart-disease">cardiovascular disease</a> and <a href='/topic.cfm?id=cancer' >cancer</a>. Much of the evidence for these associations, however, has been drawn from animal or <em>in vitro</em> research and has been somewhat controversial as to its precise implications for human health.<br />
<br />
Now, a human study has found strong links between BPA levels and semen quality&mdash;and the findings are not looking good, especially for men frequently exposed to the compound on the job.<br />
<br />
Researchers studied the urine (where BPA can be measured) and semen of 218 male factory workers in China, some of whom make BPA or put it into other products (such as plastics and epoxy resins that line cans), and the remainder, whose work did not put them in direct contact with the chemical.<br />
<br />
Compared with the control group, the men who worked in the BPA-based factories had more than four times the chance of having lowered sperm counts and more than double the risk of having lower sperm motility (swimming ability). The results of the analysis, which controlled for potentially confounding factors (including age, heavy metal and other chemical exposures, chronic disease, <a href='/topic.cfm?id=smoking' >smoking</a>, alcohol use, sexual history, etcetera), were published online October 28 in <a href="http://www.fertstert.org/"><em>Fertility and Sterility</em></a> in a study led by <a href="http://www.dor.kaiser.org/external/De-Kun_Li/">De-Kun Li</a>, a reproductive and perinatal epidemiologist at the Kaiser Permanente Division of Research in Oakland, Calif.<br />
<br />
The men in the study group who had not been exposed to BPA in the workplace nonetheless had been subject to everyday environmental contact, such as with BPA-containing food or beverage containers. But even these men, whose levels were slightly lower than those found in a typical U.S. man, showed decreased semen quality that correlated with their relative BPA levels.<br />
<br />
The precise mechanisms by which BPA might be affecting sexual function and semen quality are not yet well understood. The chemical is thought to be seen by the body as an estrogen and anti-androgen and likely disrupts hormones and hormone receptors, thus, possibly affecting hormone-dependent semen production and survival.<br />
<br />
Previous studies by Li and his colleagues had linked environmental BPA exposure in U.S. men to sexual dysfunction. The new analysis, however, presents more objective data and implies &quot;that BPA may have even more toxicity than we thought,&quot; Li says.<br />
<br />
The new findings help corroborate results from another human study published earlier this year, which found that men who had the highest levels of BPA in their urine had about 23 percent lower sperm concentrations. This study, <a href="http://www.sciencedirect.com/science?_ob=ArticleURL&amp;_udi=B6TC0-50KWFWM-5&amp;_user=10&amp;_coverDate=07%2F23%2F2010&amp;_rdoc=1&amp;_fmt=high&amp;_orig=search&amp;_origin=search&amp;_sort=d&amp;_docanchor=&amp;view=c&amp;_acct=C000050221&amp;_version=1&amp;_urlVersion=0&amp;_userid=10&amp;md5=48ce1bf17c8dbd441f910231241870b6&amp;searchtype=a">published online in July in <em>Reproductive Toxicology</em></a>, had recruited male subjects via a fertility clinic. <a href="http://www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=meekerj">John Meeker</a>, an assistant professor of environmental health sciences at the University of Michigan School of Public Health, who led the July study and was not involved in the newest research, notes that the latest work from Li's group helps strengthen the case that BPA might not just be passing inertly through our bodies.<br />
<br />
Li hopes that his team's work will help add to a growing body of literature that suggests current regulatory standards for BPA concentrations are outdated. &quot;U.S. regulation is way out of whack,&quot; Li says. The men in his team's study who worked in the BPA-processing <a href='/topic.cfm?id=plants' >plants</a> had median concentrations of about 38.7 micrograms of BPA per liter of urine, which was about 40 times higher than the control group (which had about 1.4 micrograms per liter&mdash;lower than average U.S. male levels, 2.3 micrograms per liter). Current U.S. regulatory standards, however, place daily intake limits at about 70 times the amount (2,687.5 micrograms per liter) that the BPA factory workers had. The U.S. Food and Drug Administration is in the process of <a href="http://www.scientificamerican.com/article.cfm?id=fda-shares-growing-concern-about-bpa">reviewing current safety data</a> on the chemical, and as of this March the U.S. Environmental Protection Agency had <a href="http://www.scientificamerican.com/blog/post.cfm?id=bpa-a-chemical-of-concern-epa-makes-2010-03-30">listed it as a &quot;chemical of concern.&quot;</a><br />
<br />
Both Li and Meeker emphasize the importance of consistent findings in human studies, which &quot;gives you some more confidence in the existence of an association,&quot; Meeker says. And, says Li, &quot;Our findings are consistent with animal studies,&quot; which can provide clues as to the biological processes behind the changes.<br /> </p> <br/>
	            
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							<dt>1. <a>stueysplace</a>
							
							<span class="datestamp">09:02 PM 10/28/10</span></dt>
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								<p>As always the greatest scientific discoveries are by accident.  We are trying to find a solution to one problem and we discover the solution to another.  The discovery that BPA reduces sperm count is the ultimate solution to populastion control and hence the ultimate defense against anthropogenic climate change.  This has got to trump post it notes, another accidental discovery, a failed glue that wouldn't stick very well.  We must put BPA in everything.  We could add it to municipal water supplies and in all barbeque steaks and steak sauces, oh, and I almost forgot beer.  BPA must be added to beer.  We finally have a tool that will give us the power to fight over population, and it sure beats the alternative solution, starvation.</p>
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							<dt>2. <a>ssarryo</a>
							
							<span class="datestamp">11:36 PM 10/28/10</span></dt>
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								<p>Wow, stueysplace!  Sarcastic much!?</p>
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							<dt>3. <a>stueysplace</a>
							
							<span class="datestamp">11:59 PM 10/28/10</span></dt>
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								<p>Sarcastic?  Perhaps, or is it realistic?  Still too many skeptics and deniers.  We know the problem but we refuse to face it head on.  How about banning the sale of gasoline driven cars starting in 2012.  Barely enough time for the automakers to retool. Or how about banning the burning of fossil fuels starting in 2015?  We have the technology and the job creation would be enough to bring North America out of the recession.  How about starting the conversion of skyscrapers into vertical green houses on the south facing walls?  How about requiring that all citizens must live within walking distance of their employment?  How about eliminating garbage and making everything recyclable right down to the rib bones and coffee grounds and dead flies from last nights supper?  How's about starting to do something significant to at least slow down our march to extinction?  Does no one understand that with all the species that are going extinct at an accellerating rate thet we too are a species, and a pretty stupid one at that?  &quot;Intelligence ~ the curse given the few that forces them to witness mankinds march to extinction while being pulled helplessly along by the crowd. ~Stuey&quot;</p>
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							<dt>4. <a>JamesDavis</a>
							
								<span class="in-reply-to">in reply to <a href="#comment-03">stueysplace</a></span>
							
							<span class="datestamp">07:45 AM 10/29/10</span></dt>
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								<p>&quot;stueysplace&quot;, you caught on pretty quick there. You must not have been exposed to too much BPA.<br /><br />West Virginia is doing its part in population control and lowering intelligence with BPA. They opened a plastics plant a couple of years ago that uses very large quantities of BPA in drinking bottles, including plastic baby bottles. BPA coupled with all the pollution West Virginia spews into the water, air, and land from coal and natural gas fracking has granted West Virginia the &quot;Most Stupid State&quot; in the nation award every year for the last 147 years or its 147 year existence. West Virginia has done such a great job at helping control population growth that we have to import our sperm from Hati and Cuba. So if Hati has another earthquake, it could devastate our population.</p>
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							<dt>5. <a>willaimhill</a>
							
							<span class="datestamp">11:12 AM 10/29/10</span></dt>
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								<p>The game is how to catch the sperm...Kidding aside..How does it effect the brain??Is this really a serious health disorder in the future???Forgive me,im not good with this medical terms and etc.&lt;a href =http://truevigrxplusreviews.com&gt;BPA Exposure &lt;a/&gt;<br /></p>
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							<dt>6. <a>jgrosay</a>
							
							<span class="datestamp">04:14 PM 10/29/10</span></dt>
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								<p>Probably soy phitoestrogens decrease semen and other male sexual traits quality too...</p>
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							<dt>7. <a>R.Blakely</a>
							
							<span class="datestamp">04:30 PM 10/29/10</span></dt>
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								<p>We should worry about the phenols in our computers instead of in our baby bottles. Computers stink with phenol, and so we probably are poisoned by our computers and not by out tin cans.</p>
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							<dt>8. <a>Andira</a>
							
								<span class="in-reply-to">in reply to <a href="#comment-07">R.Blakely</a></span>
							
							<span class="datestamp">08:24 PM 10/29/10</span></dt>
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								<p>Why instead? Are the alternatives really mutually exclusive? Try both.</p>
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							<dt>9. <a>Ralf123</a>
							
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							<span class="datestamp">08:27 PM 10/30/10</span></dt>
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								<p>Looks like WV is the place where the plant causes the least damage, so it made sense to build it there? Just like Louisianans love BP for the jobs and midwest farmers love Monsanto for the corn yield.</p>
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							<dt>10. <a>al</a>
							
							<span class="datestamp">10:43 AM 11/1/10</span></dt>
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								<p>EPA and FDA will bow to Corporate, as they usually do.</p>
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							<dt>11. <a>ladams14640</a>
							
							<span class="datestamp">12:40 PM 11/1/10</span></dt>
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								<p>Im pretty sure stuey has no idea what he is talking about. Im suprised he isnt pulling a stunt like the last brainwashed fool who shot up the discovery channel a month ago.<br /><br />Look the U.N.s own statistics make it clear... Any nation that becomes a 1st world nation will slowly drop off in population because of the increase in standard of living... Its a fact. Also, another fact is that the U.N.s own statistics show that the planet will top off by 2019 and will begin to lower in population, drastically... <br /><br />If you need evidence look at America , the UK, and any other nation that has become a 1st world nation for 10 years or more. America doesnt even replace its own pop... <br /><br />BPA doesnt just lower sperm count it hyper-feminizies  women and causes them to go thru puberty by the age of 9... It also feminizes Boys....<br /><br />Look, they have done studies with Bulls... These bulls were fed Estrogen Mimickers (BPA is a estrogen mimicker) which demonstrate that the Bulls began to act like cows and they attempted to throw themselves sexually at other Bulls...<br /><br />Its common sense, you stick a bunch of synthetic, unneccesary, Estrogen in animals and awful things happen.<br /><br />Stuey... Go read and learn before you spew out ignorant theories...<br /><br />Why dont you go read the climate gate scandal and how the emails showed that GLOBAL WARMING's own HQ (East Anglia) admits that their stats are going against their own predicted theory..<br /><br />They expected the planet to warm up but by the aggrigated sum total, the fact of the matter is the planet has been cooling for the past 10 years. <br /><br />GO READ A BOOK. How about Obama's Science Czar's book... its called ECO-SCIENCE and it is a 1,100 page text book about how the ruling elite in the world MUST drop population, even though UN's own numbers show they don't... You would fit in with them</p>
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							<dt>12. <a>cbutleruf</a>
							
								<span class="in-reply-to">in reply to <a href="#comment-01">stueysplace</a></span>
							
							<span class="datestamp">09:44 AM 11/2/10</span></dt>
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								<p>I entirely agree with your comment.  It's upsetting that people can't take it seriously or choose to take something like what you've said with a grain of salt.  I want more serious discussion on the matter and seeing others with similar sentiment is one of the few things that pleases me these days.</p>
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